feat: log authorized signer on init and update (#473)

Co-authored-by: frisitano <35734660+frisitano@users.noreply.github.com>

Author: yiweichi

crates/chain-orchestrator/src/consensus.rs

@@ -63,14 +63,24 @@ impl SystemContractConsensus {
     /// Creates a new [`SystemContractConsensus`] consensus instance with the given authorized
     /// signers.
     pub fn new(authorized_signer: Address) -> Self {
+        tracing::info!(
+            target: "scroll::consensus",
+            "Initialized system contract consensus with authorized signer: {authorized_signer}"
+        );
         Self { authorized_signer, metrics: SystemContractConsensusMetrics::default() }
     }
 }
 
 impl Consensus for SystemContractConsensus {
     fn update_config(&mut self, update: &ConsensusUpdate) {
         match update {
-            ConsensusUpdate::AuthorizedSigner(signer) => self.authorized_signer = *signer,
+            ConsensusUpdate::AuthorizedSigner(signer) => {
+                tracing::info!(
+                    target: "scroll::consensus",
+                    "Authorized signer updated to: {signer}"
+                );
+                self.authorized_signer = *signer
+            }
         };
     }